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A car, starting from rest, accelerates in the +x direction as in the figure. It has a mass of 1.10 x10^3 kg and maintains an acceleration of +4 m/s^2 for 5.5 s. Assume that a single horizontal force (not shown) accelerates the vehicle. Determine the average power generated by this force.

User LaVepe
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The average power generated by the force is approximately \( 48364.7 \, \text{W} \).

The average power (\(P_{\text{avg}}\)) can be calculated using the formula:

\[ P_{\text{avg}} = \frac{W}{\Delta t} \]

where:

- \( W \) is the work done,

- \( \Delta t \) is the time interval.

The work done is given by:

\[ W = F \cdot d \]

where:

- \( F \) is the force,

- \( d \) is the distance.

The force can be found using Newton's second law:

\[ F = m \cdot a \]

Given that the car maintains an acceleration (\( a \)) of \( +4 \, \text{m/s}^2 \) for \( 5.5 \, \text{s} \), and the mass (\( m \)) of the car is \( 1.10 \times 10^3 \, \text{kg} \), we can find the force (\( F \)):

\[ F = m \cdot a \]

\[ F = (1.10 \times 10^3 \, \text{kg}) \cdot (+4 \, \text{m/s}^2) \]

Now, calculate \( F \):

\[ F = 4.40 \times 10^3 \, \text{N} \]

Now, the work done (\( W \)) is:

\[ W = F \cdot d \]

The distance (\( d \)) can be found using the kinematic equation:

\[ d = v_i \cdot t + \frac{1}{2} a \cdot t^2 \]

Since the car starts from rest (\( v_i = 0 \)), the equation simplifies to:

\[ d = \frac{1}{2} a \cdot t^2 \]

Substitute the values:

\[ d = \frac{1}{2} \cdot (+4 \, \text{m/s}^2) \cdot (5.5 \, \text{s})^2 \]

Now, calculate \( d \):

\[ d = 60.375 \, \text{m} \]

Now, substitute \( F \) and \( d \) into the work formula:

\[ W = F \cdot d \]

\[ W = (4.40 \times 10^3 \, \text{N}) \cdot (60.375 \, \text{m}) \]

Now, calculate \( W \):

\[ W = 2.659 \times 10^5 \, \text{J} \]

Now, substitute \( W \) and \( \Delta t \) into the power formula:

\[ P_{\text{avg}} = \frac{W}{\Delta t} \]

\[ P_{\text{avg}} = \frac{2.659 \times 10^5 \, \text{J}}{5.5 \, \text{s}} \]

Now, calculate \( P_{\text{avg}} \):

\[ P_{\text{avg}} \approx 48364.7 \, \text{W} \]

Therefore, the average power generated by the force is approximately \( 48364.7 \, \text{W} \).

User Adem ?Lhan
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